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• Three.js video texture displays green on Chrome mobile, wrong encoding ?

  19 mai 2015, par beeb

  I am trying to make a video texture "skybox" that works on mobile browsers with Three.js. So far, I’ve been able to implement this and it works great on desktop browsers. The problem is, when viewing the animation in Chrome mobile (42.0.2311.111 on Android 5.0.2), the video appears all green with a few artifacts. I tried with mp4 (encoded with ffmpeg libx264) and ogv (ffmpeg libtheora) videos and they both fail to work (mp4 is green as stated, and ogv doesn’t display at all - black). Is the encoding the problem or webgl ? The strange thing is that my method is the same as this method : http://jeromeetienne.github.io/threex.videotexture/examples/videotexture.html
  But my Chrome mobile browser can play this example fine, so I’m guessing the encoding must be the problem ?

  Here are the command lines I used to generate the videos :

  ffmpeg -framerate 30 -i %05d.png -c:v libtheora -qscale:v 8 -r 30 outputfile.ogv
  
  ffmpeg -framerate 30 -i %05d.png -c:v libx264 -qscale:v 8 -r 30 outputfile.mp4

  Here’s the full code, even though I don’t think the problem originates from this : https://jsfiddle.net/rufn75ef/ (you have to hit the play button, autoplay doesn’t work on mobile so I disabled it for this example)

  video = document.createElement('video');
  
  video.crossOrigin = "Anonymous";
  
  var canPlayMp4 = document.createElement('video').canPlayType('video/mp4') !== '' ? true : false;
  
  var canPlayOgg = document.createElement('video').canPlayType('video/ogg') !== '' ? true : false;
  
  if (canPlayMp4) {
  
      video.src = 'vid.mp4';
  
  } else if (canPlayOgg) {
  
      video.src = 'vid.ogv';
  
  } else {
  
      alert('Your browser can\'t play video, please view this site in a modern desktop browser.');
  
  }
  
  video.muted = true;
  
  video.loop = true;
  
  
  
  video.width = 358;
  
  video.height = 264;
  
  
  
  video.load(); //do after source change
  
  
  
  videoTexture = new THREE.Texture(video);
  
  videoTexture.minFilter = THREE.NearestFilter;
  
  videoTexture.magFilter = THREE.NearestFilter;

  If you are able to test, do you experience the same problem ? How should I encode my videos using ffmpeg to maximize mobile compatibility ?

  Thanks in advance

• Try out the latest Piwik 3.0.0 beta version : Piwik 3.0.0 is almost here !

  15 novembre 2016, par Matthieu Aubry — Uncategorized

  Dear Piwik community,

  We are excited today to announce our publicly available Piwik 3.0.0 beta 3 release. We have been been working hard behind the scenes on the new 3.0.0 release for almost one year now. We, the passionate team at Piwik, are dedicated to bringing you a new and improved Piwik experience and invite you to join our beta channel to switch to Piwik 3 today !

  Enable the beta release channel

  Ready to enjoy a much faster Piwik experience and the magic of a modern user interface ? Follow the instructions here and you can upgrade to Piwik 3.0.0 beta in just one click.

  Please note that beta versions have a risk of containing bugs so we don’t recommend to use on a production server. If you find and report a bug in a beta version, we will aim to fix it as quickly as possible.

  Premium plugins in Piwik 3

  In the Piwik Marketplace you can discover & download plugins to enrich the functionality of your Piwik, as well as themes to change the look and feel of your Piwik user interface. The Marketplace integration was much improved in this new release, most notably : you can now purchase and download Premium plugins within Piwik !

  Important changes

  The Piwik 3 upgrade comes with some important changes that may require your attention which we detail in this blog post and in the developer changelog.

  The full list of more than 150 changes can be found in the Piwik 3 beta changelogs : beta 1, beta 2, beta 3.

  What to do next

  When you use the Piwik beta channel and if you come across any issues in Piwik such as a bug, feature missing, regression… let us know on our tracker and create a new issue so we can get this sorted.

  As we are in the final days of Piwik 3 development, we are looking forward to your feedback and help testing !

  Welcome to the future of Piwik,

  Happy Analytics !

• The First Problem

  19 janvier 2011, par Multimedia Mike — HTML5

  A few years ago, The Linux Hater made the following poignant observation regarding Linux driver support :

  Drivers are only just the beginning... But for some reason y’all like to focus on the drivers. You know why lusers do that ? Because it just happens to be the problem that people notice first.

  And so it is with the HTML5 video codec debate, re-invigorated in the past week by Google’s announcement of dropping native H.264 support in their own HTML5 video tag implementation. As I read up on the fiery debate, I kept wondering why people are so obsessed with this issue. Then I remembered the Linux Hater’s post and realized that the video codec issue is simply the first problem that most people notice regarding HTML5 video.

  I appreciate that the video codec debate has prompted Niedermayer to post on his blog once more. Otherwise, I’m just munching popcorn on the sidelines, amused and mildly relieved that the various factions are vociferously attacking each other rather than that little project I help with at work.

  Getting back to the "first problem" aspect— there’s so much emphasis on the video codec ; I wonder why no one ever, ever mentions word one about an audio codec. AAC is typically the codec that pairs with H.264 in the MPEG stack. Dark Shikari once mentioned that "AAC’s licensing terms are exponentially more onerous than H.264′s. If Google didn’t want to use H.264, they would sure as hell not want to use AAC." Most people are probably using "H.264" to refer to the entire MPEG/H.264/AAC stack, even if they probably don’t understand what all of those pieces mean.

  Anyway, The Linux Hater’s driver piece continues :

  Once y’all have drivers, the fight will move to the next layer up. And like I said, it’s a lot harder at that layer.

  A few months ago, when I wanted to post the WebM output of my new VP8 encoder and thought it would be a nice touch to deliver it via a video tag, I ignored the video codec problem (just encoded a VP8/WebM file) only to immediately discover a problem at a different layer— specifically, embedding a file using a video tag triggers a full file download when the page is loaded, which is unacceptable from end user and web hosting perspectives. This is a known issue but doesn’t get as much attention, I guess because there are bigger problems to solve first (c.f. video codec issue).

  For other issues, check out the YouTube blog’s HTML5 post or Hulu’s post that also commented on HTML5. Issues such as video streaming flexibility, content protection, fullscreen video, webcam/microphone input, and numerous others are rarely mentioned in the debates. Only "video codec" is of paramount importance.

  But I’m lending too much weight to the cacophony of a largely uninformed internet debate. Realistically, I know there are many talented engineers down in the trenches working to solve at least some of these problems. To tie this in with the Linux driver example, I’m consistently stunned these days regarding how simple it is to get Linux working on a new computer— most commodity consumer hardware really does just work right out of the box. Maybe one day, we’ll wake up and find that HTML5 video has advanced to the point that it solves all of the relevant problems to make it the simple and obvious choice for delivering web video in nearly all situations.

  It won’t be this year.